The possible instruction set names returned by isalist(1)
and the SI_ISALIST command of sysinfo(2) are listed here.

The list is ordered within an instruction set family in the sense that later names are generally faster then earlier names; note that this is in the reverse order than listed by isalist(1) and sysinfo(2). In the following list of values, numbered entries generally represent increasing performance; lettered entries are either mutually
exclusive or cannot be ordered.

SPARC Platforms

Where appropriate, correspondence with a given value of the -xarch option of Sun's C 4.0 compiler is indicated. Other compilers may have similar options.

1a. sparc

Indicates the SPARC V8 instruction set, as defined in The SPARC Architecture Manual, Version
8, Prentice-Hall, Inc., 1992. Some instructions (such as integer multiply and divide, FSMULD, and all floating point operations on quad operands) may be emulated by the kernel on certain systems.

1b. sparcv7

Same as sparc. This corresponds to code produced with the -xarch=v7 option of Sun's C 4.0 compiler.

2. sparcv8-fsmuld

Like sparc, except that integer multiply and divide must be executed in hardware. This corresponds to code produced with the -xarch=v8a
option of Sun's C 4.0 compiler.

3. sparcv8

Like sparcv8-fsmuld, except that FSMULD must also be executed in hardware. This corresponds to code produced with the -xarch=v8 option of
Sun's C 4.0 compiler.

4. sparcv8plus

Indicates the SPARC V8 instruction set plus those instructions in the SPARC V9 instruction set, as defined in The SPARC
Architecture Manual, Version 9, Prentice-Hall, 1994, that can be used according to The V8+ Technical Specification. This corresponds to code produced with the -xarch=v8plus
option of Sun's C 4.0 compiler.

5a. sparcv8plus+vis

Like sparcv8plus, with the addition of those UltraSPARC I Visualization Instructions that can be used according to
The V8+ Technical Specification. This corresponds to code produced with the -xarch=v8plusa option of Sun's C 4.0 compiler.

5b. sparcv8plus+fmuladd

Like sparcv8plus, with the addition of the Hal SPARC64 floating multiply-add and multiply-subtract instructions.

Like sparcv9, with the addition of the UltraSPARC I Visualization Instructions.

7b. sparcv9+fmuladd

Like sparcv9, with the addition of the Hal SPARC64 floating multiply-add and multiply-subtract instructions.

Intel Platforms

1. i386

The Intel 80386 instruction set, as described in The i386 Microprocessor Programmer's Reference
Manual.

2. i486

The Intel 80486 instruction set, as described in The i486 Microprocessor Programmer's Reference Manual. (This is effectively
i386, plus the CMPXCHG, BSWAP, and XADD instructions.)

3. pentium

The Intel Pentium instruction set, as described in The Pentium Processor User's Manual. (This is effectively i486, plus the
CPU_ID instruction, and any features that the CPU_ID instruction indicates are present.)

4. pentium+mmx

Like pentium, with the MMX instructions guaranteed present.

5. pentium_pro

The Intel PentiumPro instruction set, as described in The PentiumPro Family Developer's Manual. (This is effectively
pentium, with the CMOVcc, FCMOVcc, FCOMI, and RDPMC instructions guaranteed present.)